About half-way through my graduate school experience my main adviser decided that he was more interested in philosophy than economics. I understood this as I was an undergraduate philosophy minor, and it was in fact a philosophy course that peaked my intellectual interests first. But I was by this time wanting to make contributions to economic science, not philosophy. Nevertheless, my years involved with sports had taught me if the coach says to do that, you listen and do that. So I started reading philosophy again, attending philosophy classes, went to philosophy seminars, and spoke with professional philosophers. Then my adviser was interested in how phenomenological hermeneutics was translated back into the practice of social science. This lead to discussions with sociologists and anthropologists as well as philosophers. At the same time I was doing all this extra-curricular reading and discussing, I was also finishing up economics course work, teaching economics, and writing a dissertation in the field of Soviet economics history (I was also taking Russian language courses from the mid-1980s to about 1995, but I never could get to a point where I really knew the language). I was once asked by a prospective employer about my graduate school activities "You published a lot and on a wide set of topics, don't you think you could have finished faster had you just focused on your thesis?" Keep in mind that I defended my thesis in 4 1/2 years and it was published as a book within a year after I defended. My reply was: "I could not have written my thesis without all the other stuff in methodology, history of thought, and conceptual theory." I didn't get the job so my answer wasn't good enough.
I did take a job at a state university in Michigan --- Oakland University. The economics faculty there was (is) actually a very active though conventional group of applied economists. It was a great place to start a career because they supported me and tolerated my strange research agenda (I was at the time the only person doing 'theory'), but they also put strong expectations for publishing and quality teaching on me. The chair at the time -- Ron Tracy -- told me, I needed to publish 6 articles in 6 years in journals such as SEJ to REStat to earn tenure. I did tell him at the time that I really loved the challenge, but he should know that if I achieved that standard in addition to what I was already achieving professionally I would not be teaching at Oakland University. Ron looked at me somewhat strangely for my answer, but also smiled knowing what I was saying. This was an active research environment. Richard Hofler (now of U of Central Florida) and Kevin Murphy -- no not THE Kevin Murphy, but still a really great empirical economist and genuinely great guy -- set the standard in the department to live up, and senior faculty such as Miron Stano, a significant health economist in his own right, was a great mentor to me. Still, the very first seminar I gave at Oakland University once I was on the faculty was to the philosophy of the social sciences workshop run by Anne Rawls (now at Bentley College).
After I left graduate school, my adviser left economics to move into "cultural studies" and as I moved from Oakland to NYU and then to Stanford and back to NYU with a layover at Boston University, I picked up both an interest in economic sociology and rational choice political science to go along with my interests in market process theory, constitutional political economy, and continental philosophy and the implications for the philosophy of the social sciences. But Don Lavoie's move into "cultural studies" freaked me out. And Peter Berger once asked me if I ever could envision myself as something other than an economist. I answer yes, and he laughed and said "No you can't." Berger was right of course. I do think the battle over economics as a discipline is not only a worthy fight, it is a critical battle. But we can talk about that some other time. Why did Lavoie deciding to switch out of economics per se bother me so beyond the point Berger was alluding to?
The reality is that I didn't believe his Program on Social and Organizational Learning (PSOL) would work. And the reason for my doubts were expressed to him at the time as follows: "Don, the Committee on Social Thought at U of Chicago had faculty like Knight and Hayek and they had a hard time finding jobs for their students, what do you think PSOL is going to be able to do at GMU?" Don never answered me.
But my practical concern for the students resulted from my own reflections on what I found lacking in all my ventures ---- agreed upon standards of argument. Interdisciplinary work, while interesting, lacked standards upon which to judge contributions. It fell between the cracks. An old joke within the Austrian camp always had that if you spoke to a historian he would say of Murray Rothbard, "yes he writes a lot of history, but it isn't really good, but I understand he is a great political philosopher." And when you would talk to political philosphers they would say "Yes he writes a lot of political philosophy, but it isn't really good, but I understand he is a great economist." And finally, when you would talk to economists they would say "yes, he write a lot of economics, but it isn't really good, but I understand he is a great historian." Now those of us who already agree with him, might find him a great economist, philosopher and historian, but his contributions fall between the cracks because those in the respective fields don't find his work up to the standards of their field. Once I understood this, my life as an academic changed.
Rather than interdisciplinary, the goal was to be multi-disciplinary. If I was going to write a piece of history, I wanted historians to value the contribution. If I was going to write a piece of philosophy, it had to live up to the standards set by philosophers. And if I was going to write in political science or sociology, I wanted those in those disciplines to think I had met their disciplinary test. Finally, as an economist I wanted to write economics that other economists found interesting and worthwhile.
This is what I have tried to tell my students --- write multi-disciplinary work, not interdisciplinary.
It is also my advice to young students that have broad interests. I congratulate them on the breadth of their interests and intellectual curiosity. But there is no substitute for disciplinary training. If you are going to write philosophy, then talk to philosophers, learn to write like a philosopher, and submit your work to philosophy journals. In fact, pursue a career in philosophy, not economics. If you want to do political science, then pursue an education in political science, learn the standards of the discipline. If you want to do history, learn how to do history, write like a historian, think like a historian, etc. Now where does that leave strange programs in economics like GMU? Remember, GMU is the BEST weird place to study economics in the world and the reason is that we provide student the opportunity to learn economics and also practice the discipline at the edges of these other disciplines (philosophy, history, politcal science, sociology, etc.). My seminar at GMU is actually entitled "Workshop in Philosophy, Politics and Economics". But again I want to stress that the relevant message is one of multi-disciplinary research not interdisciplinary.
Who sets the standard in this approach? Amartya Sen, James Buchanan, Albert Hirschman come immediately to mind as economists who met the highest professional standards in philosophy, politics and economics. Joel Mokyr, Avner Greif, etc. achieved this in economics and history. Timur Kuran fits the bill with his work not only in economics and political science, but also Islamic studies. Among the Austrians, Hayek comes the closest to being the exemplar. In fact, that is part of my synthesis effort within Austrian economics that I try to communicate to the students --- Hayekian in scholarly style, Misesian in substantive contribution; Popperian (conjectures and refutations) in writing, Misesian (apriorism and deductive logic) in thought. Do that, and combine it with meeting the highest disciplinary standard of your intended audience, and you will track truth more effectively and achieve professional success as a scholar. Anything short of that, and you will find instead frustration.
Hayek once remarked that nothing is as dangerous as an economists who does only economics. True, but mere dabbling in other disciplines doesn't fix the problem. Serious study requires hard (but enjoyable) work.